1. Technical Field
The present invention relates to locating an object. More particularly, the invention concerns methods and systems for locating an object, for example a vehicle in a parking lot.
2. Description of Related Art
Almost everyone that drives a car or truck has had the frustrating experience of leaving a store, movie theater, stadium, or entertainment park, and walking into a large parking lot, and not remembering where they parked their vehicle. Searching for a vehicle in a large parking lot can be time consuming, frustrating, and dangerous. Searching for a vehicle can be particularly dangerous at night, or when the user is accompanied by small children.
Some vehicles are equipped with a small, hand-held remote device, and corresponding circuitry attached to the vehicle, which can be used to lock or unlock the vehicle's doors, to unlock the vehicle's trunk, to activate or deactivate a vehicle security system, or to execute a panic function. The small, hand-held device is sometimes called a “fob”. Typically, a fob can be attached to a keychain. The fob and the corresponding circuitry attached to a vehicle, may provide limited assistance when attempting to locate the vehicle. Typically, a fob may have one or more buttons, and when a button on a fob is pressed, the fob emits a radio frequency signal, which may be received by a radio frequency receiver attached to the vehicle. The radio frequency receiver attached to the vehicle may be connected to additional circuitry on the vehicle that performs functions associated with the buttons on the fob. In some instances, pressing a button on a fob will cause a transducer on the vehicle to emit a chirping sound, and/or will cause some lights on the vehicle to briefly illuminate. For example, the panic function may cause the vehicle's horn to sound, and may also cause some exterior lights on the vehicle to flash. Some of the functions may, to a limited extent, help a user locate a vehicle. In this regard, the panic function, or a function that activates the chirping sound, or a function that causes lights to illuminate, may be utilized to provide some assistance when attempting to locate a vehicle.
Some vehicles are equipped with a Global Positioning System (GPS) receiver, which is attached to the vehicle. In some instances the GPS receiver may transmit vehicle location information to a pager or to a wireless telephone (using a data link). These systems report the GPS-determined vehicle location information over commercial pager networks or wireless telephone networks. Operation of these GPS based systems is generally not limited by the distance between the vehicle and the user. A user may use vehicle location information transmitted to a pager or a wireless telephone, to help the user find the vehicle.
Known systems that can be employed to help a user locate a vehicle suffer from several shortcomings. For example, a shortcoming of fob based systems is the limited range of operation. Known fob based systems operate only over short distances, and typically have a maximum operating range of approximately 15 to 46 meters (approximately 50 to 150 feet) between the fob and the vehicle, and consequently are not helpful for locating a vehicle unless the vehicle is already near the fob. Another shortcoming of known fob based systems is that the chirping sound that can be emitted from the vehicle is not loud enough to facilitate locating the vehicle if the user is not already near the vehicle. Another shortcoming of known fob based systems is that, when a panic function is activated, the sound emitted from the vehicle is excessively loud when heard by a user that is near the vehicle. Another shortcoming of known fob based systems is that, when a system is used to cause sound to be emitted from the vehicle, the sound is very similar to the sounds that may be emitted from other vehicles, and this can result in confusion when two or more people are searching for their vehicles in a parking lot at the same time. Another shortcoming of fob based systems is that they generally are expensive.
Known GPS based systems also have a number of shortcomings. One shortcoming is the high cost of obtaining and operating these systems. For example, a user must purchase a costly vehicle mounted GPS system, and hardware for transmitting the GPS location information, and must also purchase a pager or telephone for receiving the GPS location information, and must also subscribe to a paging or wireless telephone service, and must also pay monthly usage fees for the paging or wireless telephone service. Another shortcoming of known GPS based systems is that presenting the GPS data in a useful format, such as a graphical map, requires an expensive smart phone, or a portable computer or Personal Digital Assistant (PDA) that has wireless capability. Another shortcoming of known GPS based systems is the limited location accuracy, which is generally about 30 feet. Another shortcoming of known GPS based systems is that the GPS may not function when the vehicle is located in an enclosed or underground structure.
Another shortcoming of both known fob and GPS based systems is that they typically require expensive, professional installation. In summary, known systems for locating a vehicle are often inadequate.